Cam wedge power clamp



Jan. 9, 1968 l.. F. BLATT CAM WEDGE POWER CLAMP Filed June 215, 1966 INVENTOR LELAND F. BLATT ATTORNEYS United States Patent O 3,362,703 CAM WEDGE POWER CLAMP Leland F. Blatt, 24121 Mound Road, Grosse Pointe, Mich. 48236 Filed June 23, 1966, Ser. No. 559,796 1 Claim. (Cl. 269-233) ABSTRACT F THE DISCLOSURE A work clamp or hold down clamp used for holding workpieces and generally power actuated characterized yby the use of an enclosing housing which protects the mechanism of the clam-p from injury and dirt.

This invention relates to cylinder operated power clamp and more particularly to improved actuating linkages for such clamps.

It is an object of this invention to provide an improved power clamp having a high mechanical advantage.

It is a further object of this invention to provide an improved power clamp having a simplified and reliable operating linkage.

Other objects, advantages and novel features of this invention will become apparent from the following specification, when considered in conjunction with the accompanying drawings.

In these drawings:

FIG. l is a plan view of the power clamp of this invention.

FIG 2 is a side elevational view of the clamp of FIG. l.

FIG. 3 is a sectional view taken in the direction of arrows 3 3 of FIG. 2.

Referring now to the drawings, the device of this invention comprises generally a bifurcated body 1t) secured to the end of power cylinder 12 by four bolts 14. Power cylinder 12 may be either a hydraulically or pneumatically operated piston or a solenoid. The assembly may be secured to a supporting structure by a base 16 provided with holes for mounting bolts.

The clamp arm 18 is pivotally mounted on body 10 by pivot bolt 2t). Clam-ping arm 18 is illustrated without any particular fixture at its upper end portion, it being understood that the particular fixture used in conjunction with this assembly does not form a part of this invention.

A pair of roller cams 22 rides in a follower slot 24 formed in the lamping arm 18. These roller cams are carried by roller pin 26 secured to the opposed arms of clevis 28.

Clevis 28 is in turn rigidly connected to the end of piston rod 30, and is mounted for reciprocating movement within guide slots 32 formed in the opposed inner faces of the legs of bifurcated body 1i). A pair of guide rollers 34 is mounted on the outer ends of roller pin 26. Rollers 34 ride in slots 32 and provide smooth and easy reciprocation of clevis 28 in body 10.

In operation, actuation of the power cylinder 12 upon a predetermined signal causes leftward movement of piston rod 3G and clevis 28 from the position shown in the lee figures. This in turn causes roller cams 22 to move toward the left end of follower slot 24.

Because of the inclination of slot 24 with respect to the axis of reciprocation, clamping arm 18 is forced to pivot clockwise about bolt 20, as viewed in FIG. 2. A subsequent actuation of power cylinder 12 causes the process to be repeated in the reverse direction, with clamping arm 18 pivoting counterclockwise about lbolt 20 until it is in the position shown in the figures. n

It Will be apparent that the power clamp of this invention provides a simple linkage with a minimum of moving parts while creating a high mechanical advantage. Clamping arm is dimensioned relative to the gap between the opposing porti-ons of body 10 to provide substantially no space between the side faces of the arm and the inner opposed faces of the body, so as to eliminate the possibility of foreign matt-er and debris entering the mechanism and fouling the mechanism. Furthermore, the positioning of the roller cams between the clevis legs, and the positioning of the guide rollers outside the clevis legs provides an extremely rigid assembly.

This invention may be further developed within the scope of the following claims. Accordingly, the above description is to be interpreted as illustrative of only a single operative embodiment, rather than in a strictly limited sense.

I now claim:

1. A clamp comprising:

a bifurcated body having opposed adjacent parallel portions having on their inner surfaces parallel alined grooves extending longitudinally, each groove having upper and lower faces providing enclosed tracks, with the third faces of the grooves being imperforate to enclose and conceal parts in the body grooves and between the body portions; the body also having a central longitudinal bore;

a clevis mounted for reciprocating motion in said bore and having spaced legs, a roller axle transversely connecting said legs and provided with guide rollers rolling in said body groove tracks and having between the guide rollers a cam roller;

a clamping arm pivotally mounted between opposed portions of the body, with the pivotal axis being transverse to and offset from said axle; and having a follower slot offset from said axis; the axle passing transversely through said slot, and the cam roller being within said slot; whereby reciprocation of said clevis causes the guide rollers to guide it longitudinally and the cam roller to cam the edges of the clamp slot and rock the clamping arm on its pivot axis.

References Cited UNITED STATES PATENTS 8/l958 Blatt et al. 269-35 3/1963 Blatt 74-107 UNITED STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No. 3,362,703 January 9, 1968 Leland P. Blatt It is hereby certified that error appears in the above numbered patent requiring correction and that the Said Letters Patent should read as corrected below.

In the heading to the printed specification, lines 3 and 4 for "Leland P. Blatt 24121 Mound Road, Grosse Pointe Mich. 48236" read Leland F. Blatt, Grosse Pointe, Mich.

(24121 Mound Road, Warren, Mich. 48092) column 2, line 44, for "transverse" read n parallel Signed and sealed this lst day of April 1969.

(SEAL) Attest:

Edward M. Fletcher, J r. EDWARD J. BRENNER Atteting Officer Commissioner of Patents 

